The MartinLogan Dynamo 1500x subwoofer carries a frequency response of 20 to 200 hertz, a low-pass filter at 40 to 150 hertz, a 650-watt amplifier and an impedance of 20,000 ohms. The MartinLogan Dynamo 300 subwoofer offers a frequency response of 32 to 150 hertz, a low-pass filter at 45 to 150 hertz, a 75-watt amplifier and an impedance of 10,000 ohms.
Other subwoofer specs besides the frequency response, low-pass filter frequency, amplifier power and impedance also affect the sound and quality of the product. Examples of other subwoofer specifications include the structural components used to make the low-frequency transducer, whether the transducer is sealed or ported, the phase controls and any room-correction capabilities the subwoofer may feature.
For example, the MartinLogan Dynamo 1500x features a sealed transducer design with a polypropylene cone in a cast aluminum basket. The Dynamo 300 uses the same structural materials but features a ported design. Subwoofers that are ported feature an extra hole through which the transducer pushes air, while sealed designs feature a sealed inner cavity that changes the nature of the sound produced by the speaker. The Dynamo 1500x offers three types of phase control, while the Dynamo 300 offers only two, and only the Dynamo 1500x offers room-correction capabilities.